net/bnxt: fix link update

net/bnxt: fix link update

1. When port is stopped, we can forcibly set the link status for the
   device to down.
2. VFs and MH PFs do not have the privilege to bring the link down.
   As a result driver prints "Link Up" when port is stopped.
3. When driver receives link status/speed/config async event from fw,
   driver invokes bnxt_link_update() with exp_link_status as ETH_LINK_UP
   This is not logically correct as the async event could be for Link up
   or link down or for speed change.

Fixes: 074cacb9907a ("net/bnxt: fix link during port toggle")
Cc: stable@dpdk.org
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>